Azure-iot-sdk-csharp: RegistryManager.UpdateTwins2Async method doesn't work when trying to update a module twin

[galmicrosoft]

• OS, version, SKU and CPU architecture used: Windows 10 Desktop x64
• Application's .NET Target Framework : net462
• Device: Laptop
• SDK version used: Microsoft.Azure.Devices.1.16.0

Description of the issue:

RegistryManager.UpdateTwins2Async method doesn't work when trying to update a module twin, instead it updates the device twin itself.
I checked with Fiddler, and the request body indeed lacks the moduleId property. I added it manually and sent the request again and the module twin updated as expected.

Code sample exhibiting the issue:

var twin = new Twin();
twin.ModuleId = "mymod";
twin.DeviceId = "device1";
twin.Tags = new TwinCollection();
twin.Tags["mytag"] = "tag";
var rm = RegistryManager.CreateFromConnectionString("<connstring>");
rm.UpdateTwins2Async(new List<Twin> { twin }, true).Wait();

[CIPop]

Thanks for reporting @galmicrosoft ! We'll need to take a look to see why this isn't working.

[luyaok]

It seems can't update module twin. I use the following code:

var moduleTwin = await registryManager.GetTwinAsync(deviceID, moduleID); moduleTwin.Properties.Desired["key"] = "value"; var updatedTwin = await registryManager.UpdateTwinAsync(moduleTwin.DeviceId, moduleTwin, moduleTwin.ETag);

When I use moduleTwin.ETag it gives me the following error:

PreconditionFailedException: Precondition failed: {"Message":"ErrorCode:PreconditionFailed;ETag mismatch for device ID 'edgedevicev2'","ExceptionMessage":"Tracking ID:0d8be9a5ec3f4de5ac4ab7ba289ac840-G:0-TimeStamp:08/10/2018 03:23:13"}

When I use device twin Etag it update device twin but not module twin.

Is it able to update module twin?

[az-iot-builder-01]

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[saikovvuri]

Hello,
Wanted to point out that the fix was made to updatetwin2sync method and not updatetwinsync method which still doesn't work for me